Immunitat und Infektion最新文献

In clinical medicine mere colonization with yeasts is often hardly to be discriminated from true infection. Thus, a clear-cut separation of preventive from therapeutic use of antimycotics is not possible in practical medicine. The problem is that on the one hand one has no exact diagnosis of yeast infection, but on the other hand best therapeutic results are obtained when the drugs are given as early as possible. In comparison to the huge number of antibacterial compounds, the members of antimicrobials are limited. For prophylaxis, one can use the polyenes, such as amphotericin B and nystatin, or the azoles, such as fluconazole or itraconazole. Thereby the azoles act not only locally at the site of application but are absorbed and thus are distributed to remote sites, where the non-resorbable polyenes never arrive. Among the azoles, fluconazole has the advantage that resorption is independent from an acid pH in the stomach, whereas itraconazole resorption is variable in severely ill persons with neutralized gastric fluid. For therapeutic use systemically applied amphotericin B has certain disadvantages. Because of toxic reactions an optimal dose cannot be given; furthermore in some sites insufficient concentrations are achieved, particularly in the kidney and also in the CSF. In contrast, the azoles possess better pharmacologic and toxicologic properties. Resistance to antimycotics is principally possible but still rare, so that in practice a routine testing is not necessary. Candida glabrata as well as Candida krusei are primarily resistant to fluconazole.

95% of individuals who come in contact with M. leprae do not develop an overt disease. It begins as an indeterminate form that may undergo spontaneous cure or may progress to different forms of leprosy (TT, BT, unstable form of BB, BL, or LL). The clinical form of the disease correlates with the T cell mediated immune response rather than to the direct damage caused by the bacilli. The lack of cellular immunity in lepromatous patients relates specifically to M. leprae. Current aspects of etiology, transmission, epidemiology, classification, clinical features, immunopathology, chemotherapy, treatment of reactions, immunotherapy and vaccination are elucidated and discussed.

Diabetic patients suffer from recurrent episodes of infections. The cellular and the humoral elements of the defense system against germ invasion are disturbed by the diabetic metabolism. Neuropathy and vascular damage promote the development of wounds and inhibit their healing. Altered motility of the gastrointestinal and the urinary tract lead to increased penetration of bacteria even there. Rare bacteria, atypical courses and frequent complications of infections result in delayed diagnosis and therapy. Dehydration, electrolyte disturbances, malnutrition, and reduced general conditions even increase susceptibility to an infection. On the other hand, an infection deteriorates the metabolic situation in diabetes, resulting in the need for higher insulin doses, or insulin injections in patients normally on oral medication. Altered every-day-life with modified food intake and reduced physical activity complicate diabetes therapy. Neuropathy, angiopathy, retinopathy, nephropathy and other diabetic complications can be triggered and aggravated during the course of an infection. To disrupt this vitious circle of hyperglycemia enforcing infections, which then raise blood glucose, it is necessary to know about the characteristic features of the interactions of diabetes and infection.

Canaliculitis is a relatively rare dacryocanal infection which occurs most unilateral. It can easily be misinterpreted and not sufficiently treated. Typical agents of the canaliculitis are actinomyces, that can cause infections of the hollow spaces with formation of concrements. The clinical courses of two patients are shown. One of them was treated for a dacryocystitis for 3 years and the other one had been referred to the eye hospital for chalazion removal. Only a microbiologic examination including cultivation of the surgically obtained dacryolithes and secretion enabled us to a reliable proof of the actinomyces and to an appropriate therapy for canaliculitis.

Bartonella henselae is an etiologic agent of cat-scratch disease and, in immunocompromised patients, of bacillary angiomatosis and other severe syndromes. Cat-scratch disease usually presents as lymphadenopathy, which resolves spontaneously within 2-4 months. The utility of antibiotic therapy remains controversial. In Tyrol four cases of human cat-scratch disease were diagnosed in children in 1994, yielding a prevalence of 0.7/100,000 per year. A 3-year-old boy had lymphadenitis coli since one year despite antituberculosis therapy which was initiated because of the histopathological picture and a positive tuberculin reaction (despite negative mycobacteria-cultures and -PCR). Two girls, age 9 and 13 years, had lymphadenitis at upper or lower extremities after cat-scratches from kittens. A 13-year-old boy presented with febrile illness and right hip pain, computer tomography revealed an osteolytic lesion; symptoms subsided within 3 weeks. Diagnosis of cat-scratch disease is based on cat contact, negative studies for other similar diseases, characteristic histopathologic features (if available), and results of an indirect immunofluorescence test (antigen: Houston-1 isolate, ATCC 49882). We believe that the availability of this serological test will increase the number of diagnosed cases of human Bartonella henselae infections.

Endogenous, nontraumatic clostridial myonecrosis has a frequent association with colon carcinoma, leukemia, diabetes mellitus, and drug-induced immunosuppression. We present two cases of Clostridium septicum myonecrosis. An 18-year-old girl developed severe abdominal pain on day 7 after hospitalization for cytostatic treatment of acute lymphoblastic leukemia. Blood cultures yielded Clostridium septicum and histopathological exam of muscle tissue showed extended myonecrosis. Eventually the patient recovered with antibiotics and surgical therapy. A 72-year-old diabetic woman was treated as an outpatient with an intramuscular injection of steroidal antiphlogistics for "acute lumbar disc disease". The next morning persistence of hip pain and discoloration of the right thigh caused hospitalization under the suspected diagnosis "fracture of the neck of the femur". Clostridium septicum was cultured from intraoperatively taken swabs. At autopsy, in addition to the gangrene, there was an adenocarcinoma of the cecum, which had not been diagnosed during life.

Diabetes mellitus is one of the most frequent metabolic distortions predisposing for infectious diseases. Characteristic features of patients with diabetes mellitus are dysfunctions of professional phagocytes, in particular of polymorphonuclear leucocytes. Infections of skin and soft tissue in particular of the lower extremities, rhinocerebral mucormycosis, invasive external otitis and urinary tract infections are typically associated with diabetes mellitus. Frequently, a rapidly progressive infection requires urgent surgical intervention and parenteral antimicrobial therapy. Short-interval metabolic controls, improvement of metabolic functions, extended vaccination and strict hygiene measures are supportive to prevent infections or to reduce a complicated outcome of infections.

For survival of plants, animals as well as main in a nature full of aggressive microbes, endogenous antibiotics play an essential role, which is not yet fully appreciated in medicine and science. For example in the granules of polymorphonuclear granulocytes and macrophages or even of specialized epithelial cells such as Paneth cells in the crypts of the intestinal mucosa, oligopeptides are produced with a wide range of antimicrobial activity. According to their chemical structures and modes of action they can be grouped into various different families. The physiological role of these agents on the surface of skin and mucosa or within host tissue is only incompletely understood.